Stock loading device for a screw machine



Oct. 10, 1961 c. E. HEMINGWAY STOCK LOADING DEVICE FOR A SCREW MACHINE Filed April 25, 1958 7 Sheets-Sheet 1 INVENTOR. CHARLES E. HEmmGu/AY Maw ATTORNEY 7 SheetsSheet 2 Filed April 23, 1958 m ms m m ATToRrJEY Oct. 10, 1961 c. E. HEMINGWAY 3,003,650

STOCK LOADING DEVICE FOR A SCREW MACHINE Filed April 25, 1958 '7 Sheets-Sheet 3 I i g LJ 3, '5 3? o I x 1 I H N O a INVENTOR. qmugs E. HsmmawAY Kai/MM A'r'ro RNEY Oct. 10, 1961 c. E. HEMINGWAY STOCK LOADING DEVICE FOR A SCREW MACHINE Filed April 25, 1958 7 Sheets-Sheet 4 INVENTOR. CHARLES E.. nsmmsway ATTORNEY Oct. 10, 1961 c. E. HEMINGWAY STOCK LOADING DEVICE FOR A SCREW MACHINE Filed April 2a, 1958 7 Sheets-Sheet 5 INVENTOR. 014m 5. rlsmua l Armada! Oct. 10; 1961 c. E. HEMlNGWAY 3,003,660

STOCK LOADING DEVICE FOR A SCREW MACHINE Filed April 25, 1958 7 Shee ts-Sheet 6 INVENTOR. uss E. llemmswnY Ar-romlexf Isl Oct. 10, 1961 c. E. HEMINGWAY STOCK LOADING DEVICE FOR A SCREW MACHINE 7 Sheets-Sheet 7 Filed April 23, 1958 zsz Fh (Mme-s E. HsmmGvJAy Maw United States Patent 3,003,660 STOCK LOADlNG DEVICE FOR A SCREW MACHINE Charles E. Hemingway, Wyandotte, Mich. (30446 Prescott, Romulus, Mich.) Filed Apr. 23, 1958, Ser. No. 730,418 Claims. (Cl. 221-75) This invention relates to automatic screw machines and more particularly to an automatic magazine stock loader therefor.

It is the object of the present invention to provide in conjunction with the elongated tubular stock reel of a screw machine, an elongated door hinged to said reel normally closing the same, together with an intermittently reciprocal link for opening and successively closing said door.

In conjunction therewith the present invention provides an automatic magazine stock loader positioned upon and along the side of the door parallel thereto, together with power operated means for opening the door when the bar of stock has been used up and at the same time activating the magazine stock loader for dropping a new bar of stock into the stock reel, and thereafter closing the reel door.

It is therefore an object of the present invention to provide an automatic magazine stock loader for the stock reel of a screw machine.

It is the object hereof to provide in said loader means whereby individual bars of stock may be intermittently delivered to the interior of the stock reel through an elongated opening adjacent the top thereof.

it is the further object herein to provide power means for intermittently energizing the automatic stock loader and for opening and closing the stock reel door in timed relation.

It is a further object of the present invention to provide a power means for the automatic magazine stock loader under the control of the reciprocal feed plunger within the stock reel, whereby upon its return movement after completing feeding a length of stock, emptying the reel, such return will activate a power operated means associated with the stock loader.

It is the further object to provide a bar end control feeding attachment for a screw machine whereby when the feed plunger pushes the last piece of stock through and out of the screw machine collet, said feed plunger is further effective through a suitable switch bracket and the chuck fork to operate a reversing switch connected with the motor drive of the feed plunger conveyor whereby the feed plunger is returned longitudinally of the stock reel to inoperative position ready to receive hte next bar of stock from the magazine loader.

The above described switch bracket operates in conjunction with the pivotal chuck fork of the screw machine whereby as the fork opens the collet, the motor reversing switch is activated after which means are employed for disengaging said switch control from the chuck fork.

It is a further object of the present invention to provide in conjunction with the final feed movement of the plunger an additional switch for stopping the back shaft of the screw machine and all machine operations until a new bar of stock has been loaded.

It is the further object of the present invention to incorporate in the screw machine forwardly of the stock reel and in advance of the screw machine spindle a bar end control together with manual or automatic means for releasing the bar end control jaws.

It is the further object of the present invention to provide a novel construction of control cam in conjunction with the screw machine and the stock feed adapted for controlling the chuck operating fork whereby the stock receiving collet in the spindle remains open a longer time compared with the closed time in order to permit the automatic feeding of longer increments of stock and to speed up the screw machine operation.

These and other objects will be seen from the following specification and claims in conjunction with the appended drawings in which:

FIG. 1 is a side elevational view of a screw machine.

FIG. 2 is a section taken on line 2--2 of FIG. 1 illustrating the association of the automatic magazine stockloader.

FIG. 3 is a fragmentary section taken on line 3-3 of FIG. 2 illustrating the chuck fork control of the feed clutch.

FIG. 4 is a fragmentary elevational section of the automatic magazine stock loader shown in FIG. 2, but on an enlarged scale.

FIG. 5 is a similar fragmentary view illustrating the operation of the loader.

FIG. 6 is a schematic fragmentary view of the power means for said loader.

FIG. 7 is a fragmentary elevational section of the stock plunger operated control for the power means of said loader.

FIG. 8 is a section taken on line 8-8 of FIG. 7.

FIG. 9 is a fragmentary side elevational view taken on line 99 of FIG. 4.

FIG. 10 is a section taken on line 10-10 of FIG. 1 illustrating the feed plunger control stop.

FIG. 11 is a fragmentary plan View thereof.

FiG. 12 is a fragmentary elevational section of the spindle assembly of the present screw machine.

FIG. 13 is a side elevational view on an enlarged scale of the control cam for the screw machine shown in FIG. 1.

FIG. 14 is a plan view of the bar end control associated with the stock reel of FIG. 1.

FIG. 15 is a section taken on line 15-15 of FIG. 14.

FIG. 16 is a fragmentary side elevational view of the manual release for the bar end control.

FIG. 17 is a fragmentary plan view of the latch for partially closing the slotted portion of the stock reel.

FIG. 18 is a fragmentary section taken on line 18-18 of FIG. 17.

FIG. 19 is a fragmentary elevational view of an improved form of operating arm for the feed clutch control shown in FIG. 3.

FIG. 20 is a fragmentary side elevational view of the feed plunger operated control means for reversing feed and for disengaging the back shaft of the screw machine at the end of feeding of a bar of stock.

FIG. 21 is a fragmentary plan view thereof with associated stock reel and feed plunger.

FIG. 22. is a fragmentary side elevational view of an automatic bar end control attachment for the screw machine.

FIG. 23 is a fragmentary plan view thereof.

It will be understood that the above drawings illustrate merely several preferred embodiments of the invention for illustration and that other embodiments are contemplated within the scope of the claims hereafter set forth.

The present application is a continuation in part of my :copending patent application, Serial Number 658,- 478, filed May 8, 1957, relating to a stock feed for a screw machine.

Referring to FIG. 1, there is shown a conventional type of screw machine to which the present invention is applied. This machine includes a conventional bed 11 on suitable legs, and mounted thereon the upright machine bed plate 12 having conventional horizontally disposed ways 13.

Turret slide 14 is mounted upon said ways and carries the conventional turret 15 which is adapted to index through an are 360 degrees and which carries a series of stock operating tools and the stop 16. A suitable hand wheel is shown at 17 by which the turret slide may be adjusted in a conventional manner. Mounted upon bed plate 12 are a pair of upright spaced journals 18 which receive hollow elongated spindle 19 which is of a conventional construction and is shown on an enlarged scale in FIG. 12.

Said spindle includes a pair of spaced driving means 20 such as pulleys whereby the spindle may be rotated by a suitable power mechanism forming a conventional part of the screw machine. Accordingly this mechanism is not further described.

There is provided in longitudinal ali nment with spindle 19 the horizontally elongated stock reel 21. Its forward end is fixedly mounted upon the block 22 upon platform 24. Platform 24 has mounted thereon the bracket 23 for supporting the shaft bushing 42 hereafter described. Said platform has supports 25 depending therefrom mounted upon the lower platform 26, whose downturned end portion 27 is secured at 2329 to the screw machine. There is also provided a motor platform 31) which extends horizontally from platform support 27 and is suitably secured thereon as at 36, FIG. 1. A conventional electric motor 31 is anchored at 32 upon platform 31] and has the usual driveshaft 33 and drive pulley 34. Bracket 35 is secured at 35 to the outer end of stock reel 21, and is pivoted at 37 within stirrup 33, which is adjustably secured at 39 upon upright standard 40 whose base 41 rests upon the ground surface G.

Bracket 23, FIG. 2 has mounted upon the top thereof journal 42 through which rotatably extends 43 carrying the differential pulley set 44 secured thereon. Upon the opposite side of journal 42 on shaft 43 there is mounted and secured another pulley 45.

Spaced longitudinally from pulley 45 there is provided'a' second pulley 5th in substantial horizontal alignment, journaled and supported at 49 upon stirrup 48 which projects upwardly from bracket 46. This bracket is secured at 47 towards the outer endof stockreel 21, and may be adjustable longitudinally thereon for taking up any slack in the belt 51 which extends around pulleys 45 and 5t). Pulleys 45 and 5t) and belt 51 may be replaced by sprocket wheels and a chain, if desired.

The lower flight of belt 51 at its free ends is secured at 53 and 54 to the upright arm 52 which is slidably positioned through the horizontally elongated slot 55 formed throughout the top of stock reel 21. The feed plunger 56, FIG. 1, longitudinally slides within the stock reel and spindle 19.

Positive means are provided for initially retaining the feed plunger drive arm 52 against forward movement at the beginning of the operation and while the stock re ceiving chuck is open. For this purpose, there is provided, referring to FIGS. 10 and 11, towards the outer end of stock reel 21, the substantially circular elongated bracket 68 secured to the stock reel by set screws 69. Said bracket includes the laterally directed support 70 Within which is slidably mounted the stop 71, Whose forward tapered end 72, FIG. 11, normally projects immediately forward of arm 52 when at its rearmost position. Stop 71 is normally retained in this position by coiled spring 73 and spring retainer 74 secured within support 70.

As viewed in FIG. 11, the horizontally disposed cantilever 75 is pivoted at 76 upon the extension 77 on support 70. The rearward arm 78 of the cantilever is arranged upon one side of the upright operating bar 71' which forms a part of stop 71 and projects thereabove.

Initial rotary movement of the cantilever in a clockwise direction under the thrust of cable 82 joined to said cantilever arm 81 at 83 will produce a lateral movement to the right of stop shaft 71 disengaging its forward end from plunger actuating arm 52, so that the latter on activation of belt 51 will move longitudinally transmitting a longitudinally thrust to feed plunger 56.

The undersurface of arm 78 has a cam 116 which on continued movement of cantilever 75 engages the cam 115 on support 71}, in effect lifting the cantilever arm 78 out of engagement with the upright bar 71', disengaging and releasing the same.

This pivotal movement of cantilever 75 is produced by a thrust to the right of cable 82 in FIG. 1. The cable at its opposite end is connected at 84 to the upright fork 85, pivoted at 86 to plate 86'. In the manner hereafter described, when the collet 101 FIG. 12 is opened releasing the stock S, the fork 85 will be tilted to the right in a clockwise direction from position in FIG. 1.

This thrust is transmitted to cantilever 75, FIG. 11 causing a clockwise rotation against the action of coiled spring 79, which is joined at one end of the cantilever arm 81 and at its other end is anchored at to support 70.

As shown in FIG. 11, the initial pivotal movement of cantflever arm 73 merely withdraws the stop 71 to disengage the conveyor drive arm 52. Additional movement in the same direction brings cam 116 into operative registry with stationary cam 115 lifting cantilever arm 78 and releasing stop 71 so that it is free to return after the passage of arm 52, to the same relative position shown in FIG. 11, and under the action of spring 73. It is noted, however, that the arm 52 is now free of stop 71. Cam surface 146 on return of arm 52 engages the tapered end 72 of stop 71 camming it out of the way.

Fork includes inwardly directed studs 87 adapted for operative engagement with chuck sleeve 88, FIGS. 1 and 12 slidably adjustable upon chuck lever fulcrum sleeve 89. A pair of opposed chuck levers 90 are positioned within sleeve 89, and their forward ends 91 are fulcrumed at 92 on said sleeve. Their opposite ends eX- tend outwardly through slots 93 in sleeve 39 and terminate in cams 94.

Stock S extends loosely between levers 90. Sleeve 89 is mounted on the reduced end of spindle 19, which is transversely slotted at 95 to receive portions of said levers. Projections 96 on levers 9t operatively engage the chuck shoe 97 within spindle 19, in a conventional manner.

Movement to the left of chuck sleeve 88 under the control of fork 85 causes the cam surfaces 98' of said sleeve to engage cams 94 on levers 91), moving their ends radially inward. Levers 90, fulcrumed at 9192, cause a longitudinal movement to the right of chuck shoe 97, FIG. 8.

This eifects a corresponding movement of chuck closing tube 98 and the internally tapered collet sleeve 99. This sleeve in turn cams against the externally tapered stock gripping collet 100, efi'ectively gripping the stock S within rotatable spindle 19. There it is retained during machine operations. Spindle 19 has a collet retaining nut 101 threaded upon its outer end retainingly engaging collet 1%. Movement to the right of chuck sleeve 88 under control of fork 85 releases levers 90 and in turn through shoe 97, .tube 98, sleeve 99 and collet 100 releases the stock. Sleeve 89 is adjustably secured on spindle 19 by nut 192. p

Reciprocal adjustments of chuck sleeve 88 are controlled by pivotal fork 85, FIG. 1. Continuously rotatable cam 103, FIG. 1 on power operated shaft 194 has a continuous cam groove 1135 into which is projected follower on said fork. Thus rotation of cam 103- 105 effects reciprocal pivotal movements of chuck operating fork 85, in a conventional manner.

When the fork pivots counterclockwise from its position in FIG. 1, collet 117i) closes and grips the stock. When it pivots clockwise from its position in FIG. 1 the collet and stock are released. When fork 85 pivots counterclockwise closing said collet, there will be a corresponding movement to the right, FIG. 1, or downwardly as in FIG. 3 of cam 126, whose arm 127 is joined to fork 85 as at point 166.

This is for the purpose of disconnecting the power operated drive from the control mechanism which operates conveyor belt 51, as hereafter described in detail.

latform 26 has secured thereon a pair of spaced journals 1197 which receive the ends of driven shaft 108 and which has secured thereto the differential drive pulley 169. This pulley is connected with the drive pulley 44 on conveyor chiveshaft 43 by means of belt 110, FIGS. 1 and 2.

Electric motor 31 on platform 39, controlled by suitable switching means from a suitable power source, drives the pulley 34 which is connected with the idle pulley clutch 111 by belt 112.

Clutch plate 111 is loosely journaled on shaft 108, and in FIG. 2 is shown in frictional engagement with driven clutch plate 113. Clutch plate 113 is co-axially mounted on shaft 1%, and has a mounting body 114 slidably keyed thereon at 114' in drive connection therewith. Coil spring 117 around shaft 108 is interposed in compression between collar 118 on said shaft and the longitudinally adjustable body 114 joined to the movable friction clutch plate 113.

As shown in FIG. 2, action of spring 117 has caused clutch plate 113 to be engaged in driving relation with drive clutch plate 111 to thus impart rotary movement to shaft 1118. This movement is transmitted to conveyor belt 51 through the belt 110 and pulleys 44 and 109.

Body 114 has an enlarged shoulder 119 at one end with an annular groove the-rein which loosely retains the inwardly projecting ends 120 on fork 121. This fork as shown in FIG. 3, which is in the nature of a fragmentary plan view taken on line 33 of FIG. 2, is pivoted at 122 upon the platform 26, also shown in FIG. 1, and at its outer end has pivoted thereto roller 123.

A second roller 124 is fixedly pivoted at 125 upon platform 26 and is spaced normally from roller 123 a distance less than the width of earn 126 in FIG. 3. Accordingly, as cam supporting arm 127 is moved in the direction of the arrow in FIG. 3, which would be to the right in FIG. 1, fork 121 is operatively pivoted in a clockwise direction.

This in turn through fork elements 120 moves the friction driven clutch element 114 slidably to the right on shaft 108, disconnecting driven clutch 113 from the continuously rotating driving clutch 111. This immediately interrupts the rotation of shaft 108 and the feed movement of conveyor belt 51 connected therewith.

This control movement of cam 126 was produced by the counterclockwise rotation of chuck fork 85, FIG. 1, which corresponded to the movement to the left of chuck sleeve 83 and the gripping of collet 100 with the stock S. In other words, at the moment that the stock is gripped against further longitudinal movement the power means which includes the drive clutch 111 is temporarily disconnected from the conveyor belt 51 operated through shaft 1438.

At the same time it is important to note that the drive means, including motor 31 and the drive clutch 111 is continuously rotatable. The interruption of the drive belt 51 takes place simultaneously with the closing of collet 190 gripping the stock. Thus the belt is temporrarily deactivated, otherwise it would be merely slipping upon its pulley.

Power movement of fork 85 in a clockwise direction causes the release of collet 100, and the stock S is now ready for its next incremental feed movement. .This movement of fork causes a movement to the left in FIG. 1 and upwardly in FIG. 3 of cam arm 127, shown in a modified form at 127', FIG. 19.

This withdraws the cam 126 from engagement with roller 123 on fork 121. The compressed spring 117 instantly moves the driven clutch assembly 113-114 to the left for immediate operative engagement with the continuously driven clutch 111. This is an automatic operation. Accordingly, every time the collet 1110 FIG. 12 grips the stock for the screw machine operations, the continuously operating power means is temporarily disconnected from the conveyor drive belt 51. Conversely just as soon as collet 191) releases the stock the belt is reactiviated immediately and transmits with maximum power the longitudinal feed force through arm 52 to stock feed plunger 56. This means that the power feed is substantially constant and instantaneous in its response. Nevertheless the longitudinal thrust through belt 51 is temporarily disconnected from the power drive whenever the stock gripping collet is closed.

In the illustrative embodiment of the invention a conveyor type of drive is shown in FIG. 1 for feed plunger 56. It was the reciprocal movement of chuck fork 85, FIG. 1, which controlled the automatic deenergization of the feed whenever the collet closed gripping the stock. Likewise when the collet opened releasing the stock under the control of fork 85, the feed of the plunger 56 was simultaneously activated.

The structure above defined is claimed in my copending application Serifl No. 658,478, filed May 8, 1957.

Automatic magazine stock loader The automatic magazine stock loader shown in FIG. 2 is illustrated on an enlarged scale in FIGS. 4 and 5, in association with the above described stock reel 21 shown in FIG. 1.

One side of said stock reel throughout a portion of its length is open and is provided with an elongated door 128 of arcuate cross section hingedly connected at its bottom edge at 129 to said stock reel and adapted for normally closing said reel.

The turn buckle 132 with its adjustable end portions is defined as a reciprocal link for opening and successively closing door 128. For this purpose the upper end of link 132 is pivotally connected at 131 to the lateral boss on door .128. The opposite end of said link is pivotally connected at 133 to the eccentric 134 secured to the power driven intermittently rotatable shaft 135.

As further shown in FIGS. 6 through 9 shaft 135 has secured thereon a pair of longitudinally spaced cams 136 spaced throughout portions of the length of said stock reel and to one side thereof. Gear 137 secured on shaft 135 is in mesh with a similar gear 138 secured upon a a second shaft 139 which also carries at least a pair of parallel spaced cams 140 corresponding to cams at 136 and arranged in substantial alignment therewith respectively.

The magazine stock loader includes at least a pair of longitudinally spaced upwardly inclined pillar blocks 147 which are arranged upon one side of stock reel 21 at right angles thereto. Corresponding laterally extending supports 143 are spaced directly below pillar blocks 147, parallel thereto and therefore are likewise inclined upwardly and outwardly. Each of the supports 143 has depending elongated edge flanges between which extend a pair of longitudinally spaced pins 142 carrying rollers 141.

These rollers are supportably mounted upon the upper surfaces of cams 136 and 140 whereby upon rotation of said cams there isimparted to supports 143 intermittent reciprocation at an angle corresponding to the lingitudinal axes of the cylindrical risers 144 which are joined at rigth angles to the' respective supports 143 at 145 and project outwardly therefrom.

Each of the supports 143 has a series of parallel spaced risers which slidably extend up through corresponding bores 146 in the stationary pillar blocks 147 which are secured adjacent the stock reel of the screw machine.

In the present preferred embodiment of the invention, there are described a pair of said stationary pillar blocks 147 extending throughout the length of the forward portion of the stock reel into which bars of stock or other type of stock may be dropped through the operation of the automatic magazine stock loader. It is contemplated, however, that more than two such pillar blocks can be employed.

Accordingly and in the preferred embodiment and with respect to the pair of pillar blocks above described there are formed across the top surfaces of said blocks aligned pairs of slots corresponding to and in registry with the respective bores 146.

For each pair of bores 146 in longitudinal alignment there is provided a corresponding transversely spaced pair of aligned reciprocal stock risers 144 which are slidably positioned within said bores 1 26 so that the upper ends of said pillar blocks are in registry with the above described slots across the top surfaces of said pillar blocks.

The respective upper ends of the risers 144 have arcuate cutaway portions in. the nature of a 90-degree arc and between each pair of aligned risers there is supported a similarly shaped transversely arcuate elongated trough 14-8 adapted to supportably receive throughout its length a bar of stock S.

There are also formed within the respective pillar blocks forwardly of each slot therein cutaway portions adapted to receive the elongated parallel spaced stock retaining plates 149 which extend between the pillar blocks and provide a guide means between the pillar blocks for longitudinally inserting stock in loading the stock loader from the front of the machine, i.e., facing FIG. 4.

As shown in FIG. 4, the stock retaining plate 149 closest to stock reel 21 has a downwardly tapered outwardly extending guide 150 over which the innermost bar of stock S rolls as it drops into the previously opened stock reel as shown in FIG. 5.

In the manner hereafter described, the risers are adapted for successive upward and downward automatic movement.

In the position of the parts shown in PEG. 4, each of the troughs 148 and corresponding retainer plate 149 receives an elongated bar of stock S, or this may be a tube, and it is noted that the said stock is positioned down within the aligned transverse pairs of slots formed in the top surface of the stationary pillar blocks 147.

The respective bars of stock are parallel to each other in spaced relation and parallel to the door 12-8 of stock reel 21. FIG. shows the position of the parts when the risers 14s. have been simultaneously elevated due to rotation of cams 136 and 140 substantially 180 degrees from the position shown in FIG. 4.

In PEG. 5 the respective troughs 148 including the risers 144 have moved upwardly to disengage the respective bars of stock from the respective pillar block slots and from its supporting trough 148, inasmuch as the plates 149 are stationary.

FIG. 5 shows the respective bars of stock in dotted lines as having rolled downwardly upon the top inclined surfaces of the pillar blocks but retained from further movement by the corresponding rear edges of the respective risers and troughs. That is, all but the end bar of stock S. This bar of stock is not retained by any structure and accordingly rolls downwardly over the guides 150 as indicated in dotted lines and drops into the previously emptied stock reel 21 after which and in timed relation link 1392 is effective for closing the stock reel door 128 to the position shown in FIG. 4.

During the operation of thestock loader and successively after elevation of the risers 144, the same will withdraw downwardly into the pillar blocks 147 so that the second bar of stock will roll into the outermost trough 14814? previously occupied by the bar of stock which had dropped into the stock reel. Simultaneously each of the bars of stock will successively roll by gravity forward into the next adjacent trough.

Viewing FIG. 4,.as the eccentric 134- and the corresponding cam 136 rotates approximately 180 degrees the risers 144 become elevated to the position shown in FIG. 5 and the link 132 moves downwardly opening the stock reel door 128 to the dotted line position shown in FIG. 4 or the solid line position in FIG. 5.

Power control for stock feed The power mechanism for activating the automatic stock feed magazine is particularly showin FIGS. 6, 7 and 8, and includes the geared low r.p.m. motor 156" with driveshaft 151 carrying at its end drive clutch 152 normally spaced as in FIG. 7 from the driven clutch 153 keyed at 154- upon camshaft 139. This camshaft fragmentarily shown in FIG. 7 is also shown in FIGS. 4, and 6 and is journaled at 55 and has secured thereto at least a pair of cams 141). A corresponding pair of cams 136 are secured on shaft and rotated in unison, as fragmentarily shown in FIG. 6.

Shaft 139 has a collar 57, and coiled spring 58 is interposed between said collar and the driven clutch 153 slidably keyed at 154, whereby upon release of clutch 153 from its holding pin 61 as hereafter described clutch 153 under action of spring 58 will be moved axially into operating engagement with drive clutch 152.

Clutch retaining pin 61 projects from stud 62 which extends upwardly through support 63, being secured in place by lock nut 64. Support 63 is pivoted at 65 upon standard 66 projecting upwardly from the base plate 67. Coiled spring 8 is interposed in compression between plate 67 and pivotal support 63 normally retaining plate 63 in the clutch disengaged position shown in FIG. 7. Studs 9 and 19 project through members 63 and 67 in opposed relation receiving opposite ends of spring 8.

The upper end of pin 61 operatively engages the annular cam surface 66 formed in the driven clutch 153 so that whenever plate 63 is tilted upwardly from below the position shown in FIG. 7 under the action of s ring 8, pin 61 will operatively cam against driven clutch 153 disengaging the same from drive clutch 152.

When the remainder of a length of stock has been completely used within stock reel 21 and by means of mechanism described, the stock activating plunger 56 is mechanically returned to the rear end of stock reel 21 as fragmentarily shown in FIG. 7.

Arm 161 is pivotally connected at 163 within slot 167 in the end of feed plunger 56 and has a rearwardly positioned pawl 162 which will operatively engage one of the segments 160 of ratchet 159 as said feed plunger 56 is returned to the fragmentary position shown.

Referringto FIGS. 7 and 8 ratchet 159 is journaled and mounted upon shaft 158 which extends between a pair of depending bosses 157 upon the undersurface of stock reel 21, which has a longitudinal slot 16%) adapted to receive the upper portion of ratchet 159. A pivotal control arm including a plate 63 is arranged directly below said ratchet and carries at its outer end upwardly extending stud and lock nut 155.

The upper end 156 of said stud projects above plate 63 and lies in the path of counterclockise rotation of ratchet 159. Accordingly when the feed plunger 56 has returned to the end of stock reel, pawl 162 engages ratchet 159 and the segments 160 moves in a counterclockwise direction depressing stud 156 for a short period. This causes pin 61 to become disengaged from driven clutch 153. Coil spring 58 is effective to move clutch 153 on shaft 139, upon which it is keyed into contact with drive clutch 152. 7

Accordingly the motor is effective for a short interval to drive camshaft 139 and the interconnected 9 camshaft 135. For the first half of the single revolution of shaft 139 the crank 134 has caused the link 132 to move downwardly opening door 128 of the stock reel. At the same time the cams 136 and 140 have been effective for lifting the respective risers 144 to the position shown in FIG. 5. At this point as above described, the innermost bar of stock will drop into the open stock reel.

For the remainder of the single revolution of camshaft 139 the stock reel door is closed to the position shown in FIG. 4 and the risers 144 are returned likewise to the position shown in FIG. 4. All this has taken place while one ratchet segment 160 has temporarily held pins 156- 161 in lowered position.

Just as soon as the ratchet segment 160 passes pin 156 spring 8 returns support 63 and pin 61 to the position shown in FIG. 7. Pin 61 cams against cam surface 60 of driven clutch 153 disengaging the same from drive clutch 152 and interrupting rotation of camshaft 139.

A new length of stock has been dropped into stock reel, and this operation will not be repeated until plunger 56 is again returned to the rear-most position within stock reel 21, as in FIG. 5.

Referring to FIG. 7, the stud 168 supportably engages arm 161 rearwardly of its pivot 163. Accordingly, said arm, in view of slot 167, may pivot upwardly on pivot 163. FIG. 6 is a. schematic illustration of the drive mechanism for the magazine loader.

Control cam Referring to FIGS. 1 and 13 there is provided upon power rotated shaft 104 an improved control cam 103 keyed thereto at 169 and secured by nut 170. Cam 103 previously described as the collet opening and closing cam associated with spindle 19 of the screw machine, includes the tapered and arcuately formed collet closing cam element 171 which is mounted upon the external portion of cam 103 adjacent an annular flange and secured thereto by fasteners 172.

Collet closing cam surface 173 and collet opening cam surface 174 are angularly related and are secured around an arc of the circumference of cam 103. Additional apertures 224 are provided by which cam element 171 may be adjusted with respect to the cam body.

Cam 103 also includes collet opening cam element 175 which is secured upon the opposite side of cam 103 from cam element 171, as by fastener 176, and is adjacent an annular flange. Collet opening cams 174-175 operate upon disc 105' secured at 106 at the lower end of collet control fork 85.

Upon rotation of shaft 104 and the relative downward movement of cam 175 the fork 85 is rotated in a clockwise direction for opening the spindle collet 100 shown in FIG. 12.

It will he noted that for a substantial portion of the rotation of cam 103, said collet will be maintained in an open position and the cam element 171 is effective for closing the said collet only for a small portion of the rotation of the cam as indicated by the cam surface 173. The result of this is that the earn 103 provides for feeding throughout longer portions of the cycle as no other cams have heretofore done. This gives a longer time increment for feeding stock and accordingly longer lengths of stock.

Manual release bar and control Referring to FIG. 1, there is identified a bar end control at 177 interposed between the end of stock reel 21 and spindle 19. The detail of construction of said bar end control is shown in FIGS. 14, 15 and 16.

As shown in drawings, the bar end control includes the jaw body 177 with internal axial bore 178 with tapered opening 179 adapted to slidably and loosely receive the bar stock as it leaves the stock reel and is projected into the spindle 19.

Body 177 has a pair of forwardly extending arms 180 of diiferent length between which are pivotally mounted 10 a pair of oppositely arranged jaws 181 mounted upon the transverse pivot pins 182 which span elements 180. Elongated leaf springs 183 are anchored at 184 upon the top and bottom of the jaw body and have free end portions overlying and retainingly engaging jaws 181 maintaining the position shown in FIG. 15.

The jaws have defined therebetween the opening 185 adapted to loosely receive the bar stock. Said jaws have internal recesses 186 which receive and support the gripping pads 187 anchored within said jaws by fasteners 188. The respective pads are so formed as to define therebetween the axial passage 189, which in the position of the parts shown snugly and retainingly engages the forward end of the bar stock so as to prevent its longitudinal movement upon the initial stopping of the feed plunger arm 52 when it is retained against forward movement at the outermost position indicated in FIG. 11.

Normally the feed plunger has achieved an initial momentum at the beginning of the feed movement and upon the positive stopping thereof, as indicated in FIG. 11, the bar of stock would have a tendency to continue forwardly. The purpose of the bar end control jaws is to frictionally prevent such continued movement so that feed plunger 56 stays in contact with the bar stock.

The forward inner end portions of pads 187 are tapered inwardly to guidably receive the forwardly moving bar stock in the assembly shown in FIG. 1. After its initial stopping of the stock and at the beginning of the screw machine operation, the said jaws must be separated either manually or automatically. FIGS. 14, 15 and 16 show a means of manually separating the jaws 181, whereas FIGS. 2223 show an automatic means for accomplishing this result, as will be hereafter described.

A pair of jaw opening rolls 191 are secured in vertically spaced relation at 192 to forward end portions of the respective jaws 181. There is provided a control arm 193 pivotally joined to some stationary portion of the screw machine such as upon the plate 86', FIG. 1 as at 194, FIG. 16, and includes at its upper end handle 195, fragmentarily shown. The wedge shaped body 196 is secured upon one side of arm 193 and its pointed end is arranged intermediate rolls 191. Accordingly clockwise pivotal movement of handle 195 and arm 193 will cam member 196 between said rolls and accordingly tilt the jaws outwardly about their supporting pins 182.

semicircular grooves 197 are formed upon the opposite sides of wedge 196 for cooperative retaining engagement with rolls 191 for holding said jaws in open position. The jaws will stay open until the bar of stock has been completely fed through the stock reel. Thereafter the jaws will be manually disengaged in order to serve as a bar end control for the new bar of stock supplied to the stock reel.

Closure latch for stock reel Referring to FIGS. 17 and 18, the stock reel 21 is fragmentarily shown and includes the above described longitudinal slot 55 in its top surface adapted to loosely receive the longitudinally reciprocal arm 52 connected to feed plunger 56.

In view of the movement of the stock within the stock reel and its rotation, it is advantageous to provide a closure latch to prevent accidental displacement of the stock through slot 55. For this purpose there is provided a double end latch 198 pivotally mounted at 199 upon one side of said stock reel and which includes a pair of laterally extending tapered ends 200 which are cam shaped, one of which ends overlies a portion of slot 55.

On return movement of arm 52 to the rear of reel 21 or upwardly of FIG. 17, the overlying end 200 will be cammed out of the way about pivot 199 and the other cam 200 is moved to span slot 55. Thus an effective means is provided to keep the stock from jumping out of slot 55.

Referring to FIGS. 20-21 there is provided a control mechanism and a pair of switches to be automatically operated when the feed plunger 56 in the stock reel has pushed the last piece of bar stock through and out of collet 1th), FIG. 12.

The chuck operating fork 85 is pivotally mounted at 86 to a part of the machine such as plate 36 as shown in assembly, FIG. 1. As above described, inwardly directed pins 87 at the upper end of the chuck fork are adapted to operatively engage the chuck 88, FIGS. 1 and 12 regulating opening and closing of collet 1th in a conventional manner. a

T he chuck fork shutoff bracket 202 is horizontally disposed and pivotally connected at 291 to one side of fork 35. The opposite end of said bracket includes the tapered upwardly extending pawl 2&3 adapted to slide along the tapered surface of plate 204 anchored at 2% upon upright mounting plate 297 associated with the screw machine of FIG. 1. Spring 293 interconnects the free end of bracket 2112 and plate 2%, holding pawl 2123 against plate 264.

Electric switch operating bracket 269 bears against upright plate 207 and is slidably mounted thereon by fastener 211 which extends through the elongated slot 210 in said bracket and is secured to plate 267. Spring 2112 is connected at one end to bracket 2&9. Its opposite end is anchored at 213 to plate 2117 for normally maintaining the bracket 23? in the inoperative position shown. 7 The opposite end of bracket 299 a tapered undersurface 214, which movably rests upon roll 215 projecting from plate 237. Coiled spring 215 interconnects bracket 229 with plate 2-"3-7 for maintaining said bracket at its forward end against roll 215.

Said bracket has a downwardly depending pawl 217, adapted to be operatively engaged by bracket pawl 223 when pawl 217 is lowered from the position shown in FIG. 20 into the path of return movement of pawl 2G3 under the action of pivotal chuck fork 85.

As shown in FIG. 21, the rear end of switch operating bracket 269 has a laterally extending bracket arm 218 which overlies stock reel 21 and is directly in the path of arm 52 connected at the rear of feed plunger 56. Accordingly when the feed plunger pushes the last piece of bar stock through and out of collet FIG. 12 within the machine spindle 19, said feed plunger arm 52 operatively engages and pushes bracket arm 218 causing a forward movement of bracket 2&9.

Spring 216 causes said bracket at its forward end to drop downwardly riding along its surface 214 until pawl 217 lies inthe path of bracket pawl 203. Accordingly when the chuck fork 85 moves in a clockwise direction and opens the collet 190 in the manner above described, it pulls the shutofi switch bracket 209 to the right so that its control surface 219 operatively engages button 222 of reversing switch 223 for the feed conveyor drive motor 31 shown in FIG. 2.

This has the effect through the conveyor mechanism of pulling feed plunger arm 52 away from the electric switch bracket 209 so that said bracket will return to an inoperative position under action of spring 212.

Before this return movement has taken place, however, the control surface 219 of bracket 209 has also engaged button 22%) of control switch 221. This stops the operation of the screw machine with the above mentioned collet 190, in open position. The switch 221 operates a conventional clutch to disengage the backshaft of the screw machine from its drive motor.

When switch bracket 209 returns to inoperative position, the pawl end 217 is cammed upwardly out of the path of reciprocal pawl 203 so that further movement thereof will have no effect upon reversing switch 223 or the screw machine backshaft controlling switch 221. Thus the backshaft of the screw machine and all machining operations are stopped until a new bar has been loaded into the stock reel and the backshaft reactivated.

As shown in FIG. 11, after the new bar of stock has been dropped into the stock reel and moved forwardly under the action of feed plunger 56, it is stopped initially as shown in FIG. 11. This movement of arm 52 operates a small switch 262 to restart the backshaft of the screw machine.

Automatic bar end control attachment instead of the manually operable bar end control 177 above described in FIGS. 14, 15 and 16 and fragmentarily shown in FiG. 1, there is also provided an automatic bar end control shown in FIGS. 22-23. The above described chuck fork is fragmentarily shown and its pivotal mounting 86 on plate as corresponds to FIG. 1.

Transverse bolt 225 extends through the chuck fork operated longitudinally disposed control arm 226 and is secured to the upper end of fork 85 with a suitable lock nut 227 interposed. The opposite end of horizontally extending arm 226 is slotted at 229 to receive shoulder support screw 228. Screw 228 extends through spacer 239, through elongated slot 231 in elongated jaw opener arm 232 and is secured to jaw mounting body 177' at 233. I aw opener arm 232 is parallel to arm 226.

Body 177' has a pair of forwardly extending spaced elements 23 between which extends the transverse pins 23s pivotally supporting the pair of stock gripping jaws 235. Suitable set screws 237' anchor pins 235 within the jaw body extensions 234.

Upwardly and downwardly opening slots 238 are respectively formed within the top and bottom surfaces of opposing jaws The upright bolt 239 extends loosely through said jaws at its outer ends carries at least one adjustable nut 24f). Coil springs 241 are respectively interposed between nuts 24 and the corresponding inner ends of slots 23% to normally maintain the jaws 235 in the parallel stock end gripping relation shown in FIG. 22. The spring tension can be regulated by adjusting nut 240.

The forward end of jaw body 177" has formed therethrough the axial enlarged passage 242 which is outwardly tapered at its outer end, and which would normally be positioned adjacent the forward end of stock reel 21 shown in FIG. 1, and is adapted to loosely receive the forward end of the bar of stock S.

A corresponding slot is defined between the left hand ends of jaws 235 ending in the tapered portions 243 and the restrictive passageway 245 of reduced diameter which snugly and slidably receives the end of the stock due to the action of springs 241 and jaws 235. The leading end of the bar of stock is effectively gripped by said jaws in the same manner above described in connection with FIGS. 14, 15 and 16.

I aw opener arm 232 at its right end, FIG. 22, includes the outwardly tapered jaw opener body 246 whose angular surfaces are adapted to operatively engage inner portions of the pair of opener rolls 248 secured at 249 to side portions of the two jaws 235.

In normal operation the narrow portion of jaw opener i.e., arm 232 is supportably positioned between said rolls. However, upon lateral projection to the left of the tapered jaw opener body 246, as in FIG. 22, the jaws will be cammed open. The jaw opener body includes at its top and bottom arcuate slots 247 which upon continued movement to the left of the jaw opener arm will lockingly engage with rolls 248 for maintaining the jaws in open position during normal operations and feed of the bar stock therethrough.

Stud shaft 250' is secured at 251 through one end portion of arm 226 and anchored by the lock nuts 252. The outer end of stud shaft 250 carrys the axially directed adjustable screw 253 which is in alignment with and is adapted operatively to engage the outer endof jaw opener body 2%.

Accordingly operating movement counterclockwise of 13 chuck fork 85 to the left, FIG. 22 will cause movement to the left of arm 226, stud shaft 250 and a corresponding movement of jaw opener 232246.

This movement of fork 85 causes a separation of jaws 235 and additional mechanism is provided under control of the stock feeding arm 52 for temporarily engaging the jaw opener arm 2.32 with control arm 226 so that operating movement to the right or clockwise movement of fork 85 will disengage the jaw opener body 246 from the rolls 248 permitting the jaws to receive the new bar stock introduced into the stock reel.

For this purpose cantilever 254 is pivotally mounted at 255 upon the end of stock reel 21, as shown in FIG. 22, and one arm thereof normally lies in the path of movement of feed plunger control arm 52, FIG. 23. Accordingly, when the feed plunger has reached a predetermined position, arm 52 operatively engages cantilever 254. The other arm 256 of said cantilever has nested through an end slot thereof stud 257 which extends loosely through a slot in jaw opening arm 232 and acts as a locking pin.

Coil spring 253 is interposed between arm 232 and disc 259 secured to locking pin 257. Accordingly clockwise pivotal movement of cantilever 254 will efiect an outward movement of locking pin 257 so that its end 260 projects within the tapered aperture 261 in the control arm 226. This provides a positive means of interconnecting arm 232 with chuck fork operated arm 226 so that movement to the right of arm 226 will efiect a corresponding disengaging movement to the right of the jaw opening arm 232-246.

When the feed plunger 56 comes up feeding the last of the bar stock, the arm 52 pushes the locking pin 260 into the opening 261 of control arm 226. Accordingly when this latter arm is travelling to the right, the screw machine collet is open to receive the stock. However, the jaws 235 of the bar end control are closed under the action of springs 241.

When the collet closes on movement of the fork in the opposite direction at the beginning of the screw machine operation, movement in the opposite direction of arm 226, through stud 250 and adjusting screw 253 causes movement to the left of the jaw controlling arm 232-246, opening the jaws until all the bar stock is used up. At that time, and under the action of arm 52, cantilever 254, pin 260, arms 226 and 232, the jaws close in order to be in a position to grippingly engage the new bar of stock at the beginning of the cycle.

, Having described my invention, reference should now be had to the following claims.

.I claim:

1. An automatic magazine stock-loader for a screw machine comprising a pair of longitudinally spaced pillar blocks extending angularly upward, there being a series of transversely spaced pairs of aligned slots formed across the top surfaces of said blocks, each pair of blocks adapted to receive spaced portions of a stock bar, corresponding transversely spaced pairs of aligned reciprocal stock risers slidably positioned within said pillar blocks with their upper ends registering with said slots, each pair of risers adapted to supportably engage spaced portions of a bar of stock, a laterally extending support below each pillar block parallel thereto and joined to and supporting the corresponding stock risers, power means for intermittently raising and successively lowering said supports relative to said pillar blocks, upward movement of said risers disengaging said bars of stock from said pillar blocks, whereby the bar of stock nearest the lower edges of said pillar blocks will drop therefrom, and the remaining bars of stock will roll downwardly onto said pillar blocks, retainingly engaged by forwardly adjacent elevated risers, and upon withdrawal movement of said risers drop into the forwardly adjacent slots in said pillar blocks.

2. The magazine stock loader of claim 1, said power means including pairs of aligned cams rotatable in unison 14 and supportably engaging the undersurface of each of said supports, there being one pair of cams for each support.

3. The magazine stock loader of claim 1, said power means including a pair of parallel spaced power driven shafts rotatable in unison and spaced below said supports, and a pair of spaced cams on each shaft supportably engaging said supports respectively.

4. The magazine stock loader of claim 1, and a series of parallel spaced stock receiving troughs of arcuate shape in cross section extending between and at right angles to said pillar blocks, each trough mounted respectively upon the corresponding upper ends of a pair of risers.

5. The magazine stock loader of claim 1, a series of parallel spaced stock receiving troughs of arcu-ate shape in cross section extending between and at right angles to said pillar blocks, each trough mounted respectively upon the corresponding upper ends of a pair of risers, and a series of elongated parallel spaced stock retaining plates extending between and at right angles to said pillar blocks and mounted through the upper portions thereof, laterally inward of each of said pairs of risers retainingly engaging said bars of stock respectively.

6. In an automatic magazine stockholder for a screw machine, a pair of longitudinally spaced angularly and upwardly extending pillar blocks with transversely spaced pairs of aligned slots across their top surfaces adapted to receive spaced portions of a plurality of parallel spaced bars of stock respectively, corresponding transverely spaced pairs of aligned stock risers slidably positioned within said pillar blocks with their upper ends registering with said slots, each pair of stock risers adapted to supportably engage spaced portions of a bar of stock, a laterally extending support below each pillar block parallel thereto joined to and supporting the corresponding stock risers, power means for intermittently raising and successively lowering said supports relative to said pillar blocks, said power means, including a pair of interconnected parallel spaced shafts rotatable in unison and spaced below said supports, a pair of spaced cams on each shaft supportably engaging said supports respectively, a low rpm. motor having a drive clutch in axial alignment with one of said camshafts, a driven clutch slidably keyed on said one camshaft normally retained in spaced relation to said drive clutch, spring means urging said driven clutch towards said drive clutch, a pivotal control arm, spring means normally maintaining said arm as to retain said driven clutch spaced from the drive clutch, a stock reel, an upright ratchet adjacent said arm journalled upon said reel and projecting thereinto, the teeth of said ratchet adapted upon rotation to intermittently engage said pivotal control arm to momentarily disengage said arm from said driven clutch, a reciprocal feed plunger in said stock reel, and a pawl pivotally mounted on the end of said plunger extending axially rearward thereof whereby upon return movement of said plunger to the rear of said stock reel said pawl rotates said ratchet one tooth distance, said one camshaft rotating 360 degrees.

7. In the magazine stock loader of claim 6, a pair of spaced upwardly extending studs on said arm, an annular cam surface on said driven clutch operatively engaged by one of said studs for spacing said driven clutch from said drive clutch, the other stud arranged below and lying in the path of said ratchet operatively engaged thereby intermittently.

8. In the stock loader of claim 6, a pair of spaced upwardly extending studs on said arm, an annular cam surface on said driven clutch operatively engaged by one of said studs for spacing said driven clutch from said drive clutch, the other stud arranged below and lying in the path of said ratchet operatively engaged thereby intermittently, on disengagement of said second stud by said ratchet, said arm pivotally and operatively moving said first stud operatively camming said driven clutch out of engagement with l the drive clutch.

longitudinal slot through its top surface, a feed plunger movable within said reel, an upright reciprocally movable control arm extending through said slot into said reel and joined to said feed plunger, an elongated latch pivoted intermediate its ends upon the top of said reel adjacent its slot and inclined at an acute angle thereto, cam shaped pawls overlying said slot, movement of said arm in one direction camming said overlying pawl laterally away from said slot, the pawl at the opposite end of said latch being pivoted so as to overlie said slot, return movement of said arm camming said second pawl laterally and automatically returning to first pawl to slot bridging position.

10. In a screw machine, a stock reel, means for feeding stock longitudinally thereof, and a bar end control mounted on said machine outwardly of said reel, said con trol consisting of a jaw body centrally apertured to loosely receive a bar of stock, a pair of oppositely arranged jaws pivotally mounted upon said body and grooved upon their interior surfaces defining an axial passage of reduced diameter for frictionally receiving and retainingly engaging said stock, spring means engaging said jaws for maintaining an opposed stock gripping relation there- 'between, opposed spaced rolls projecting from the one Side of said jaws forwardly of their pivotal mounting in ver tically spaced relation, and reciprocal oppositely tapered cam means adapted for forceful projection between said rolls.

11. In the screw machine of claim 10, there being opposed notches formed in said cam means retainingly engagable with said rolls for securing said jaws in opened stock release position.

12. The screw machine of claim 10, said reciprocal oppositely tapered jaw opening cam means consisting of a longitudinally reciprocal jaw opening arm slidably mounted upon said jaw body and spaced between said rolls and an oppositely tapered body at one end of said arm, an upright chuck fork pivotally mounted upon said screw machine, a longitudinally disposed control arm pivotally secured at one end to said fork and at its other end slidably mounted on said jaw body in parallel spaced relation to said jaw opening arm, means projecting laterally from said control arm adapted upon pivotal movement in one direction of said fork to project said jaw opening arm longitudinally so that said tapered body operatively engages and separates said jaws, maintaining the same open throughout feeding of stock through said reel, a transverse spring biased control pin movably mounted upon said jaw opening arm, a cantilever pivoted upon the end of reel, said stock moving means at the end of its feed movement operatively engaging said cantilever and said cantilever adapted to engage said pin moving the same into retaining registry with said control arm, whereby return movement of said fork withdraws said jaw opening arm and tapered body permiting said jaws to resiliently close.

13. In a screw machine, a stock feed plunger, a reciprocally movable arm joined to said plunger, power means for moving said arm, a support, a reversing switch joined to said power means mounted on said support, and having a button contact, a switch operating bracket slidably mounted on said support, spring means anchored to said support and joined to said bracket, normally spacing said bracket from said contact, and a control arm projecting laterally of said bracket in the path of movement in said arm at the forward end of the stock reel, a depending first pawl on the forward end of said bracket, a pivotal chuck fork, a horizontal control arm at one end pivotally joined thereto and extending below said pawl, an upwardly extending second pawl on the other end of said control arm normally spaced from said first pawl, cam means supporting one end of said bracket whereby on forward movement of said bracket, its pawl drops into interlocking engagement with said second pawl on counterclockwise movement of said fork so that on subsequent clockwise movement of fork said bracket arm is projected into engagement with said switch button.

14. In the screw machine of claim 13, a second switch on said support adapted for shutting down the screw machine, said switch having a control button lying in the path of movement of said switch bracket for activation simultaneously with activation of said reversing switch button. a

15. In the screw machine of claim 13, a second switch on said support adapted for shutting down the screw machine, said switch having a control button lying in the path of movement of said switch bracket for activation simultaneously with activation of said reversing switch button, a spindle carrying a stock gripping collet, a reciprocal chuck sleeve on said spindle joined to said chuck fork for closing and successively opening said collet on counterwise and successive clockwise movement of said fork, whereby movement of said fork shutting down said screw machine simultaneously opens said stock collet.

References Cited in the file of this patent UNITED STATES PATENTS 2,320,039 Jobert May 25, 1943 2,345,207 Mansfield Mar. 28, 1944 2,542,357 Reed Feb. 20, 1951 2,562,455 Gridley July 31, 1951 2,577,203 Mariotte Dec. 4, 1951 2,584,466 Kaserman Feb. 5, 1952 2,595,522 Harney May 6, 1952 2,626,451 Gridley Jan. 27, 1953 2,646,087 Jobert July 21, 1953 2,730,371 Pulman Jan. 10, 1956 2,746,128 Barron May 22, 1956 2,848,786 Kendall Aug. 26, 1958 2,859,290 Grinage Nov. 4, 1958 

